Process window widening using coated parts in plasma etch processes

ABSTRACT

Embodiments of the present technology may include a method of etching. The method may include mixing plasma effluents with a gas in a first section of a chamber to form a first mixture. The method may also include flowing the first mixture to a substrate in a second section of the chamber. The first section and the second section may include nickel plated material. The method may further include reacting the first mixture with the substrate to etch a first layer selectively over a second layer. In addition, the method may include forming a second mixture including products from reacting the first mixture with the substrate.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.15/670,919, filed Aug. 7, 2017, and which is hereby incorporated byreference in its entirety for all purposes.

TECHNICAL FIELD

The present technology relates to semiconductor processes and equipment.More specifically, the present technology relates to improving processselectivity during low pressure etching operations.

BACKGROUND

Integrated circuits are made possible by processes which produceintricately patterned material layers on substrate surfaces. Producingpatterned material on a substrate requires controlled methods forremoval of exposed material. Chemical etching is used for a variety ofpurposes including transferring a pattern in photoresist into underlyinglayers, thinning layers, or thinning lateral dimensions of featuresalready present on the surface. Often it is desirable to have an etchprocess that etches one material faster than another facilitating, forexample, a pattern transfer process. Such an etch process is said to beselective to the first material. As a result of the diversity ofmaterials, circuits, and processes, etch processes have been developedwith a selectivity towards a variety of materials.

Dry etches produced in local plasmas formed within the substrateprocessing region can penetrate more constrained trenches and exhibitless deformation of delicate remaining structures than wet etches.However, even though an etch process may be selective to a firstmaterial over a second material, some undesired etching of the secondmaterial may still occur.

Thus, there is a need for improved systems and methods that can be usedto produce high quality devices and structures. These and other needsare addressed by the present technology.

BRIEF SUMMARY

As semiconductor devices become smaller, patterning these devices maybecome more challenging. Smaller features may be harder to define. Thismay be a result of the decreased size or of more stringent tolerancesneeded for performance, reliability, and manufacturing throughput. Themethods described below may provide an improved patterning process.

Flowing a mixture of plasma effluents and a gas by nickel platedmaterials may allow for etching at lower pressures. Lower pressureprocessing may be advantageous for smaller and deeper semiconductorfeatures by facilitating etchants to travel to the bottom of a narrowand deep feature without contacting and etching a sidewall. Nickelplating may increase selectivity by maintaining a low etch amount ofsilicon at lower pressures. Without intending to be bound by theory, itis believed that nickel may scavenge fluorine radicals or hydrogenradicals, which may be responsible for undesired etching of silicon.Nickel may coat parts of the chamber that are downstream of significantmixing of gases and plasma etchants. Nickel and may coat all parts alongthe flow path of plasma effluents in the chamber downstream of mixing.

Embodiments of the present technology may include a semiconductorprocessing system. The system may include a remote plasma region. Thesystem may also include a processing region fluidly coupled with theremote plasma region by a channel. The system may further include a gasinlet fluidly coupled to the channel. The gas inlet may define a flowpath for a gas that does not pass through the remote plasma regionbefore entering the processing region. The processing region may includea pedestal configured to support a substrate. The processing region maybe at least partially defined by a sidewall and a showerhead. Thesidewall and showerhead may be plated with nickel.

Embodiments of the present technology may include a method of etching.The method may include mixing plasma effluents with a gas in a firstsection of a chamber to form a first mixture. The method may alsoinclude flowing the first mixture to a substrate in a second section ofthe chamber. The first section and the second section may include nickelplated material. The method may further include reacting the firstmixture with the substrate to etch a first layer selectively over asecond layer. In addition, the method may include forming a secondmixture including products from reacting the first mixture with thesubstrate.

Embodiments of the present technology may include a method of etching.The method may include flowing a first gas including ammonia and afluorine-containing gas through a plasma to form plasma effluents. Themethod may also include flowing the plasma effluents through a firstsection of a chamber. The first section may not include nickel platedmaterial. The method may further include mixing a second gas includingammonia with the plasma effluents in a second section of a chamber toform a first mixture. In addition, the method may include flowing thefirst mixture to a substrate in a third section of the chamber. Themethod may also include reacting the first mixture with the substrate toetch a silicon oxide layer selectively over a silicon layer. Then, themethod may include forming a second mixture comprising products fromreacting the first mixture with the substrate. The second mixture may beflowed through a fourth section of the chamber to exit the chamber. Thesecond section, third section, and fourth section may include nickelplated material.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the disclosedtechnology may be realized by reference to the remaining portions of thespecification and the drawings.

FIG. 1 shows a semiconductor processing system according to embodimentsof the present technology.

FIG. 2 shows a method of etching according to embodiments of the presenttechnology.

FIG. 3 shows a method of etching according to embodiments of the presenttechnology.

FIGS. 4A, 4B, and 4C show etch amounts using a nickel coated chamber andan anodized aluminum chamber according to embodiments of the presenttechnology.

FIG. 5 shows a top plan view of one embodiment of an exemplaryprocessing tool according to embodiments of the present invention.

FIGS. 6A and 6B show cross-sectional views of an exemplary processingchamber according to embodiments of the present invention.

FIG. 7 shows a schematic view of an exemplary showerhead configurationaccording to embodiments of the present invention.

FIG. 8 shows a schematic cross-sectional view of an exemplary processingsystem according to embodiments of the present technology.

FIG. 9 illustrates a schematic bottom partial plan view of an inletadapter according to embodiments of the present technology.

DETAILED DESCRIPTION

Conventional systems and methods for etching silicon oxide may not besuited for low pressures. Low pressures may be preferable for smallerand deeper semiconductor features. However, at lower pressures, etchselectivity may decrease. For example, during the etch of thermal oxideat lower pressures, the etch amount of thermal oxide may decrease, whilethe etch amount of silicon may increase. At low pressures, the densityof reactive components, such as radicals, decreases. As a result, theetch rate of thermal oxide may decrease. Unreacted or incompletelyreacted species may also be present in the chamber. At lower pressures,these unreacted species (e.g., fluorine radicals or hydrogen radicals)may react with silicon in the substrate, increasing the etch rate ofsilicon. Conventional methods etching at increased chamber pressure inorder to react the radicals with the substrate or other gaseous species.

Embodiments of the present technology may allow for low pressure etchingof thermal oxide without substantially decreasing selectivity overetching of silicon. Chamber parts plated in nickel may reduce the amountof unreacted radicals. With fewer unreacted radicals, the radicals aremore likely to etch thermal oxide and not be present to etch silicon.

I. SYSTEM OVERVIEW

As shown in FIG. 1, embodiments of the present technology may include asemiconductor processing system 100. System 100 may include a remoteplasma region. The remote plasma region may include remote plasma source102.

System 100 may also include a processing region fluidly coupled with theremote plasma region by a channel defined by isolator 104. Isolator 104may be a ceramic material, such as alumina. Isolator 104 may not beplated with nickel. The processing region may include areas of thechamber from where the gases and plasma effluents mix to where theplasma effluents react with a substrate to the exit from the chamber.The processing region may include a region from, but not includingisolator 104, to a port from the chamber to a pump.

System 100 may further include a gas inlet 106 fluidly coupled toisolator 104. The gas inlet may define a flow path for a gas that doesnot pass through the remote plasma region before entering the processingregion. Plasma effluents from plasma source 102 may enter isolator 104through inputs 108. Gas inlet 106 and inputs 108 may be disposed in aremote plasma source (RPS) adapter 110. RPS adapter 110 allows a remoteplasma source to connect to the chamber. RPS adapter 110, gas inlet 106,and inputs 108 may not be plated with nickel.

Downstream of isolator 104 is a mixing manifold 112. Mixing manifold 112may define a flow path that is not substantially straight. For example,mixing manifold may include a reduction (e.g., a taper) and/or expansionin the flow path size in order to mix the gas and the plasma effluents.Mixing manifold 112 may lead to gasbox 114. Gasbox heater 116 may bedisposed on gasbox 114.

After gasbox 114, system 100 may be configured so that the plasmaeffluents and other gases pass through uniform blocker 118, uniformfaceplate 120, and uniform selective modular device (SMD) 122. System100 may include a reaction region, at least partially defined by uniformSMD 122 and spacer 124. The reaction region may be a portion of theprocessing region.

The processing region may include a pedestal 126 configured to support asubstrate. The pedestal may be plated with nickel, but a nickel platedpedestal may not affect the selectivity of the etch as the substrate maycover the pedestal. The substrate may be a semiconductor wafer,including a silicon wafer. System 100 may include an annulus (i.e., edgering 128) disposed on the circumference of pedestal 126. The annulus maybe plated with nickel.

System 100 may include a pumping liner/channel 130. Pumpingliner/channel 130 may include an outlet from the chamber to a pump.System 100 may also include lid plate insert 132.

The processing region may include regions defined from mixing manifold112 to pumping liner/channel 130. The processing region may be at leastpartially defined by a sidewall (e.g., spacer 124 or any part that formsthe chamber wall), and a showerhead (e.g., uniform SMD 122). Thesidewall and showerhead may be plated with nickel. Some or all surfacesfrom the mixing of the gases in mixing manifold 112 to pumpingliner/channel 130 may have surfaces plated with nickel, including forexample, electroless nickel plating or nickel electroplating.Electroless nickel may include nickel with boron or nickel withphosphorous. Parts downstream of isolator 104 may have surfaces platedwith nickel. In other words, mixing manifold 112, gasbox 114, uniformblocker 118, uniform faceplate 120, uniform SMD 122, spacer 124, edgering 128, and pumping liner/channel 130 may be plated with nickel oranother metal that scavenges excess radicals. A pressure plate, an inletadapter, and a diffuser (not shown in FIG. 1, but shown in FIG. 8) maybe between isolator 104 and mixing manifold 112 and may each be platedwith nickel or another metal that scavenges excess radicals. Othermetals may include platinum or palladium, but both may be too expensive.The parts plated with nickel may include a metal other than nickelbefore plating. For example, the parts may include stainless steel oraluminum.

FIG. 1 is a simplified diagram of a system. FIG. 8 shows a similardiagram of a system and is described below. One of skill wouldunderstand that any of the parts (e.g., metal parts) in FIG. 8 from themixing of plasma effluents and gases downstream of isolator 104 (e.g.,from pressure plate 4025) to exiting the chamber may be plated withnickel.

II. METHODS

Embodiments include methods of etching, which may use the system ofetching described herein.

A. Example Method

As shown in FIG. 2, embodiments of the present technology may include amethod 200 of etching. In block 202, method 200 may include mixingplasma effluents with a gas in a first section of a chamber to form afirst mixture. The plasma effluents may include effluents from flowingammonia and a fluorine-containing gas through a plasma. Thefluorine-containing gas may include NF₃ and/or HF. In some embodiments,the plasma effluents may include effluents from flowing ammonia, NF₃,argon, H₂, helium, and HF through a plasma. The first section mayinclude nickel plated material, including electroless nickel platedmaterial. The first section may include a mixing manifold, similar tomixing manifold 112 in FIG. 1. In embodiments, the first section mayinclude a tapered path (e.g., central aperture 4023 in FIG. 8). Thetapered path may mix the gases more than a non-tapered path, which mayallow for nickel-plated parts to scavenge radicals. The gas may includeammonia or hydrogen.

Before mixing the plasma effluents, the plasma effluents may be flowedthrough a section of the chamber that does not include nickel platedmaterial. Parts of the chamber before the gas is introduced may not beplated with nickel. For example, in FIG. 1, RPS adapter 110 may not beplated with nickel. Plating the RPS adapter with nickel may decrease theamount of silicon oxide etched but increase the amount of polysiliconetched, contrary to the desired outcome. Parts of the chamber that arenot metal (e.g., ceramic) or do not allow for sufficient mixing ofplasma effluents and gas may also not be plated with nickel. Forexample, in FIG. 1, isolator 104 is ceramic and cannot be easily platedwith nickel. In addition, isolator 104 does not provide the geometry forsignificant mixing or the plasma effluents and the gas.

In block 204, method 200 may also include flowing the first mixture to asubstrate in a second section of the chamber. The second section of thechamber may be at a pressure of 10 Torr or lower, which may include 8 to10 Torr, 6 to 8 Torr, 4 to 6 Torr, 2 to 4 Torr, 1 to 2 Torr, or lowerthan 1 Torr. The second section of the chamber may include the pedestal,where the substrate may be located during processing. The second sectionmay include nickel plated material, including any nickel plated materialdescribed herein. The first mixture may flow in a path in the chamberfrom the first section to the second section. The path may be defined bynickel plated parts of the chamber. The path from significant mixing ofthe plasma effluent and the gas to the exit of the chamber may bedefined by surfaces plated with nickel, uninterrupted by surfaces notplated with nickel.

In block 206, method 200 may further include reacting the first mixturewith the substrate to etch a first layer selectively over a secondlayer. The first layer may be a thermal silicon oxide layer. The secondlayer may be a silicon layer, including a polysilicon layer. The secondlayer may be any layer that may be etched by fluorine radicals orhydrogen radicals. Reacting the first mixture with the substrate mayinclude etching less than 1 Angstrom of the second layer and greaterthan 50 Angstroms of the second layer. In embodiments, the second layermay have an etch amount of greater than 50 Angstroms, greater than 100Angstroms, 200 Angstroms, or 300 Angstroms, while the first layer has anetch amount of less than 1 Angstrom, including less than 0.5 Angstrom orabout 0 Angstroms. The selectivity of etching oxide over silicon may begreater than 100, 200, 300, 400, 500, 600, 700, 800, 900, or 1000.

In block 208, method 200 may include forming a second mixture includingproducts from reacting the first mixture with the substrate. Method 200may also include flowing the second mixture through a section of thechamber to exit the chamber, where the surface of the chamber leading toexit the chamber include nickel plated material. For example, in FIG. 1,pumping liner/channel 130 may be nickel plated.

Method 200 may include adsorbing fluorine atoms or hydrogen atoms ontothe nickel plated material. Removing the fluorine atoms or hydrogenatoms from reacting with the substrate may help maintain negligibleetching of silicon while etching thermal oxide.

Method 200 may further include removing the substrate from the chamberand performing additional patterning operations on the substrate.

B. Example Method

As shown in FIG. 3, embodiments of the present technology may include amethod 300 of etching. In block 302, method 300 may include flowing afirst gas including ammonia and a fluorine-containing gas through aplasma to form plasma effluents. The first gas may be any gas describedherein.

In block 304, method 300 may also include flowing the plasma effluentsthrough a first section of a chamber. The first section may not includenickel plated material. The first section may include parts of thechamber that are not metal or do not have sufficient mixing of plasmaeffluents and gas. The first section may be any section of the chambernot plated with nickel as described herein.

In block 306, method 300 may further include mixing a second gasincluding ammonia with the plasma effluents in a second section of achamber to form a first mixture. The second gas may not pass through aplasma before mixing with the plasma effluents. The second section ofthe chamber may be where the gases undergo sufficient mixing. Forexample, in FIG. 1, the second section of the chamber may include mixingmanifold 112. The second section of the chamber may include a taperedaperture and may include pressure plate 4025, inlet adapter 4030,diffuser 4035, and mixing manifold 4040 in FIG. 8.

In block 308, method 300 may include flowing the first mixture to asubstrate in a third section of the chamber. The third section of thechamber may include the portion of the chamber where the substrate isetched. In FIG. 1, the third section of the chamber may be at leastpartially defined by uniform SMD 122 and spacer and may include pedestal126.

In block 310, method 300 may also include reacting the first mixturewith the substrate to etch a silicon oxide layer selectively over asilicon layer. The silicon oxide layer and silicon layer may be any suchlayer described herein and may be etched as selectively as describedherein.

In block 312, method 300 may include forming a second mixture comprisingproducts from reacting the first mixture with the substrate. Theproducts may include etch byproducts from etching silicon oxide.

In block 314, the second mixture may be flowed through a fourth sectionof the chamber to exit the chamber. The fourth section of the chambermay be at least partially defined by a pump port, or for example,pumping liner/channel 130 in FIG. 1. Exiting the chamber may includeentering a section of the system at a significantly different pressurethan a section of the system configured to receive a substrate.

The second section, third section, and fourth section may include nickelplated material. The first mixture may flow in a path in the chamberfrom the second section to the fourth section. The path may becontinuous and may be defined by nickel plated parts of the chamber. Anysurface from the second section to the fourth section may be plated withnickel and may not include surfaces that are absent nickel plating. Asdescribed with FIG. 1, any and all parts from and including mixingmanifold 112 to pumping liner/channel 130, with the optional exceptionof pedestal 126, may be plated with nickel. With FIG. 8, any and allparts from and including pressure plate 4025 to exiting the chamber maybe plated with nickel.

III. EXAMPLES

Etch amounts were measured for a system without any nickel plated partsand a system with nickel plated parts. The system with nickel platedparts was a system similar to FIG. 1, with parts downstream of isolator104 plated with nickel (including mixing manifold 112, gasbox 114,uniform blocker 118, uniform faceplate 120, uniform SMD 122, spacer 124,edge ring 128, and pumping liner/channel 130, as well as a pressureplate, an inlet adapter, and a diffuser not shown in FIG. 1). RPSadapter 110 and isolator 104 were not plated with nickel. The systemwithout nickel plated parts had instead anodized aluminum coatingsinstead. A gas mixture of NH₃, NF₃, argon, H₂, helium, and HF was flowedthrough a remote plasma source. The plasma effluents were then mixedwith ammonia and flowed to etch a substrate. Etch amounts of thermaloxide and polysilicon were measured.

FIG. 4A, FIG. 4B, and FIG. 4C show the results of etching with a nickelcoated chamber and an anodized aluminum chamber. In FIG. 4A, the x-axisis the chamber pressure. The y-axis on the left shows the thermal oxideetch amount in angstroms. A higher thermal oxide etch amount is desiredfor this process. The diamonds show the thermal oxide etch amounts fornickel coatings, and the triangles show the thermal oxide etch amountsfor anodized aluminum coatings. For pressures from 7 Torr to 10 Torr,both systems show similar thermal oxide etch amounts.

The y-axis on the right shows the silicon etch amount in angstroms. Thesquares show the silicon etch amounts for nickel coatings, and the x'sshow the silicon etch amount for anodized aluminum coatings. At 10 Torr,both the nickel coating system and the anodized aluminum coating systemshow close to zero amount of silicon etched. However, as pressuredecreases, the silicon etch amount for the anodized aluminum coatingsystem increases. At 6 Torr, the anodized aluminum coating results inabout 10 Angstroms of silicon etched. By contrast, even at the lowesttested pressure of 4 Torr, the nickel coated system shows close to noamount of silicon etched.

FIG. 4B shows the results from FIG. 4A but only for the nickel coatedsystem. The graph shows thermal oxide etch amount on the left-handy-axis, silicon etch amount on the right-hand y-axis, and chamberpressure on the x-axis. The thermal oxide etch amounts are plotted, andthe thermal oxide etch amount decreases as pressure decreases. No etchamount of silicon was measured for any chamber pressure. As a result,the nickel coated system showed infinite selectivity for etching thermaloxide over silicon in this example.

FIG. 4C shows the results from FIG. 4A but only for the anodizedaluminum system. The graph shows the thermal oxide etch amount on theleft-hand y-axis, silicon etch amount on the right-hand y-axis, andchamber pressure on the x-axis. The thermal oxide etch amounts areplotted, and the thermal oxide etch amount decreases as pressuredecreases. The etch amount of silicon increases as pressure decreases.At a pressure of 7 Torr, the silicon etch amount was about 10 Angstroms,while the thermal oxide etch amount was about 250 Angstroms. Theselectivity at 7 Torr was slightly greater than 25. The results indicatethat the silicon etch amount would continue to increase and the thermaloxide etch amount would continue to decrease as chamber pressuredecreases. As a result, at pressures lower than 7 Torr, one would expectselectivities lower than 25.

IV. EXEMPLARY PROCESSING SYSTEM

Processing chambers that may implement embodiments of the presentinvention may be included within processing platforms such as theProducer® Selectra™ etch system, available from Applied Materials, Inc.of Santa Clara, Calif.

FIG. 5 shows a top plan view of one embodiment of a processing tool 1000of deposition, etching, baking, and curing chambers according todisclosed embodiments. In the figure, a pair of front opening unifiedpods (FOUPs) 1002 supply substrates of a variety of sizes that arereceived by robotic arms 1004 and placed into a low pressure holdingarea 1006 before being placed into one of the substrate processingchambers 1008 a-f, positioned in tandem sections 1009 a-c. A secondrobotic arm 1010 may be used to transport the substrate wafers from theholding area 1006 to the substrate processing chambers 1008 a-f andback. Each substrate processing chamber 1008 a-f, can be outfitted toperform a number of substrate processing operations including the dryetch processes described herein in addition to cyclical layer deposition(CLD), atomic layer deposition (ALD), chemical vapor deposition (CVD),physical vapor deposition (PVD), etch, pre-clean, degas, orientation,and other substrate processes.

The substrate processing chambers 1008 a-f may include one or moresystem components for depositing, annealing, curing and/or etching afilm on the substrate wafer. In one configuration, two pairs of theprocessing chamber, e.g., 1008 c-d and 1008 e-f, may be used to depositmaterial on the substrate, and the third pair of processing chambers,e.g., 1008 a-b, may be used to etch the deposited film. In anotherconfiguration, all three pairs of chambers, e.g., 1008 a-f, may beconfigured to etch a film on the substrate. Any one or more of theprocesses described may be carried out in chamber(s) separated from thefabrication system shown in different embodiments. Films may bedielectric, protective, or other material. It will be appreciated thatadditional configurations of deposition, etching, annealing, and curingchambers for films are contemplated by processing tool 1000.

FIG. 6A shows a cross-sectional view of an exemplary process chambersection 2000 with partitioned plasma generation regions within theprocessing chamber. During film etching, e.g., silicon, polysilicon,silicon oxide, silicon nitride, silicon oxynitride, silicon oxycarbide,carbon-containing material, etc., a process gas may be flowed into thefirst plasma region 2015 through a gas inlet assembly 2005. A remoteplasma system (RPS) unit 2001 may be included in the system, and mayprocess a gas which then may travel through gas inlet assembly 2005. Theinlet assembly 2005 may include two or more distinct gas supply channelswhere the second channel (not shown) may bypass the RPS unit 2001.Accordingly, in disclosed embodiments the precursor gases may bedelivered to the processing chamber in an unexcited state. In anotherexample, the first channel provided through the RPS may be used for theprocess gas and the second channel bypassing the RPS may be used for atreatment gas in disclosed embodiments. The process gases may be excitedwithin the RPS unit 2001 prior to entering the first plasma region 2015.Accordingly, a fluorine-containing precursor, for example, may passthrough RPS 2001 or bypass the RPS unit in disclosed embodiments.Various other examples encompassed by this arrangement will be similarlyunderstood.

A cooling plate 2003, faceplate 2017, ion suppressor 2023, showerhead2025, and a pedestal 2065, having a substrate 2055 disposed thereon, areshown and may each be included according to disclosed embodiments. Thepedestal 2065 may have a heat exchange channel through which a heatexchange fluid flows to control the temperature of the substrate. Thisconfiguration may allow the substrate 2055 temperature to be cooled orheated to maintain relatively low temperatures, such as between about−20° C. to about 200° C., or therebetween. The heat exchange fluid maycomprise ethylene glycol and/or water. The wafer support platter of thepedestal 2065, which may comprise aluminum, ceramic, or a combinationthereof, may also be resistively heated in order to achieve relativelyhigh temperatures, such as from up to or about 100° C. to above or about1100° C., using an embedded resistive heater element. The heatingelement may be formed within the pedestal as one or more loops, and anouter portion of the heater element may run adjacent to a perimeter ofthe support platter, while an inner portion runs on the path of aconcentric circle having a smaller radius. The wiring to the heaterelement may pass through the stem of the pedestal 2065, which may befurther configured to rotate.

The faceplate 2017 may be pyramidal, conical, or of another similarstructure with a narrow top portion expanding to a wide bottom portion.The faceplate 2017 may additionally be flat as shown and include aplurality of through-channels used to distribute process gases. Plasmagenerating gases and/or plasma excited species, depending on use of theRPS 2001, may pass through a plurality of holes in faceplate 2017 for amore uniform delivery into the first plasma region 2015.

Exemplary configurations may include having the gas inlet assembly 2005open into a gas supply region 2058 partitioned from the first plasmaregion 2015 by faceplate 2017 so that the gases/species flow through theholes in the faceplate 2017 into the first plasma region 2015.Structural and operational features may be selected to preventsignificant backflow of plasma from the first plasma region 2015 backinto the supply region 2058, gas inlet assembly 2005, and fluid supplysystem (not shown). The structural features may include the selection ofdimensions and cross-sectional geometries of the apertures in faceplate2017 to deactivate back-streaming plasma. The operational features mayinclude maintaining a pressure difference between the gas supply region2058 and first plasma region 2015 that maintains a unidirectional flowof plasma through the showerhead 2025. The faceplate 2017, or aconductive top portion of the chamber, and showerhead 2025 are shownwith an insulating ring 2020 located between the features, which allowsan AC potential to be applied to the faceplate 2017 relative toshowerhead 2025 and/or ion suppressor 2023. The insulating ring 2020 maybe positioned between the faceplate 2017 and the showerhead 2025 and/orion suppressor 2023 enabling a capacitively coupled plasma (CCP) to beformed in the first plasma region. A baffle (not shown) may additionallybe located in the first plasma region 2015, or otherwise coupled withgas inlet assembly 2005, to affect the flow of fluid into the regionthrough gas inlet assembly 2005.

The ion suppressor 2023 may comprise a plate or other geometry thatdefines a plurality of apertures throughout the structure that areconfigured to suppress the migration of charged species (e.g., ions) outof the plasma excitation region 2015 while allowing uncharged neutral orradical species to pass through the ion suppressor 2023 into anactivated gas delivery region between the suppressor and the showerhead.In disclosed embodiments, the ion suppressor 2023 may comprise aperforated plate with a variety of aperture configurations. Theseuncharged species may include highly reactive species that aretransported with less reactive carrier gas through the apertures. Asnoted above, the migration of ionic species through the holes may bereduced, and in some instances completely suppressed. Controlling theamount of ionic species passing through the ion suppressor 2023 mayprovide increased control over the gas mixture brought into contact withthe underlying wafer substrate, which in turn may increase control ofthe deposition and/or etch characteristics of the gas mixture. Forexample, adjustments in the ion concentration of the gas mixture cansignificantly alter its etch selectivity. In alternative embodiments inwhich deposition is performed, it can also shift the balance ofconformal-to-flowable style depositions for dielectric materials,carbon-containing materials, and other materials.

The plurality of holes in the ion suppressor 2023 may be configured tocontrol the passage of the activated gas, i.e., the ionic, radical,and/or neutral species, through the ion suppressor 2023. For example,the aspect ratio of the holes, or the hole diameter to length, and/orthe geometry of the holes may be controlled so that the flow ofionically-charged species in the activated gas passing through the ionsuppressor 2023 is reduced. The holes in the ion suppressor 2023 mayinclude a tapered portion that faces the plasma excitation region 2015,and a cylindrical portion that faces the showerhead 2025. Thecylindrical portion may be shaped and dimensioned to control the flow ofionic species passing to the showerhead 2025. An adjustable electricalbias may also be applied to the ion suppressor 2023 as an additionalmeans to control the flow of ionic species through the suppressor.

The ion suppression element 2023 may function to reduce or eliminate theamount of ionically-charged species traveling from the plasma generationregion to the substrate. Uncharged neutral and radical species may stillpass through the openings in the ion suppressor to react with thesubstrate. It should be noted that the complete elimination ofionically-charged species in the reaction region surrounding thesubstrate is not always the desired goal. In many instances, ionicspecies are required to reach the substrate in order to perform the etchand/or deposition process. In these instances, the ion suppressor mayhelp to control the concentration of ionic species in the reactionregion at a level that assists the process.

Showerhead 2025 in combination with ion suppressor 2023 may allow aplasma present in chamber plasma region 2015 to avoid directly excitinggases in substrate processing region 2033, while still allowing excitedspecies to travel from chamber plasma region 2015 into substrateprocessing region 2033. In this way, the chamber may be configured toprevent the plasma from contacting a substrate 2055 being etched. Thismay advantageously protect a variety of intricate structures and filmspatterned on the substrate, which may be damaged, dislocated, orotherwise warped if directly contacted by a generated plasma.Additionally, when plasma is allowed to contact the underlying materialexposed by trenches, such as the etch stop, the rate at which theunderlying material etches may increase.

The processing system may further include a power supply 2040electrically coupled with the processing chamber to provide electricpower to the faceplate 2017, ion suppressor 2023, showerhead 2025,and/or pedestal 2065 to generate a plasma in the first plasma region2015 or processing region 2033. The power supply may be configured todeliver an adjustable amount of power to the chamber depending on theprocess performed. Such a configuration may allow for a tunable plasmato be used in the processes being performed. Unlike a remote plasmaunit, which is often presented with on or off functionality, a tunableplasma may be configured to deliver a specific amount of power to theplasma region 2015. This in turn may allow development of particularplasma characteristics such that precursors may be dissociated inspecific ways to enhance the etching profiles produced by theseprecursors.

A plasma may be ignited either in chamber plasma region 2015 aboveshowerhead 2025 or substrate processing region 2033 below showerhead2025. A plasma may be present in chamber plasma region 2015 to produceradical-fluorine precursors from an inflow of a fluorine-containingprecursor. An AC voltage typically in the radio frequency (RF) range maybe applied between the conductive top portion of the processing chamber,such as faceplate 2017, and showerhead 2025 and/or ion suppressor 2023to ignite a plasma in chamber plasma region 2015 during deposition. AnRF power supply may generate a high RF frequency of 13.56 MHz but mayalso generate other frequencies alone or in combination with the 13.56MHz frequency.

Plasma power can be of a variety of frequencies or a combination ofmultiple frequencies. In the exemplary processing system the plasma maybe provided by RF power delivered to faceplate 2017 relative to ionsuppressor 2023 and/or showerhead 2025. The RF power may be betweenabout 10 watts and about 2000 watts, between about 100 watts and about2000 watts, between about 200 watts and about 1500 watts, or betweenabout 200 watts and about 1000 watts in different embodiments. The RFfrequency applied in the exemplary processing system may be low RFfrequencies less than about 200 kHz, high RF frequencies between about10 MHz and about 15 MHz, or microwave frequencies greater than or about1 GHz in different embodiments. The plasma power may becapacitively-coupled (CCP) or inductively-coupled (ICP) into the remoteplasma region.

The top plasma region 2015 may be left at low or no power when a bottomplasma in the substrate processing region 2033 is turned on to, forexample, cure a film or clean the interior surfaces bordering substrateprocessing region 2033. A plasma in substrate processing region 2033 maybe ignited by applying an AC voltage between showerhead 2025 and thepedestal 2065 or bottom of the chamber. A cleaning gas may be introducedinto substrate processing region 2033 while the plasma is present.

A fluid, such as a precursor, for example a fluorine-containingprecursor, may be flowed into the processing region 2033 by embodimentsof the showerhead described herein. Excited species derived from theprocess gas in the plasma region 2015 may travel through apertures inthe ion suppressor 2023, and/or showerhead 2025 and react with anadditional precursor flowing into the processing region 2033 from aseparate portion of the showerhead. Alternatively, if all precursorspecies are being excited in plasma region 2015, no additionalprecursors may be flowed through the separate portion of the showerhead.Little or no plasma may be present in the processing region 2033.Excited derivatives of the precursors may combine in the region abovethe substrate and, on occasion, on the substrate to etch structures orremove species on the substrate in disclosed applications.

Exciting the fluids in the first plasma region 2015 directly, orexciting the fluids in the RPS unit 2001, may provide several benefits.The concentration of the excited species derived from the fluids may beincreased within the processing region 2033 due to the plasma in thefirst plasma region 2015. This increase may result from the location ofthe plasma in the first plasma region 2015. The processing region 2033may be located closer to the first plasma region 2015 than the remoteplasma system (RPS) 2001, leaving less time for the excited species toleave excited states through collisions with other gas molecules, wallsof the chamber, and surfaces of the showerhead.

The uniformity of the concentration of the excited species derived fromthe process gas may also be increased within the processing region 2033.This may result from the shape of the first plasma region 2015, whichmay be more similar to the shape of the processing region 2033. Excitedspecies created in the RPS unit 2001 may travel greater distances inorder to pass through apertures near the edges of the showerhead 2025relative to species that pass through apertures near the center of theshowerhead 2025. The greater distance may result in a reduced excitationof the excited species and, for example, may result in a slower growthrate near the edge of a substrate. Exciting the fluids in the firstplasma region 2015 may mitigate this variation for the fluid flowedthrough RPS 2001.

The processing gases may be excited in the RPS unit 2001 and may bepassed through the showerhead 2025 to the processing region 2033 in theexcited state. Alternatively, power may be applied to the firstprocessing region to either excite a plasma gas or enhance an alreadyexcited process gas from the RPS. While a plasma may be generated in theprocessing region 2033, a plasma may alternatively not be generated inthe processing region. In one example, the only excitation of theprocessing gas or precursors may be from exciting the processing gasesin the RPS unit 2001 to react with the substrate 2055 in the processingregion 2033.

In addition to the fluid precursors, there may be other gases introducedat varied times for varied purposes, including carrier gases to aiddelivery. A treatment gas may be introduced to remove unwanted speciesfrom the chamber walls, the substrate, the deposited film and/or thefilm during deposition. A treatment gas may be excited in a plasma andthen used to reduce or remove residual content inside the chamber. Inother disclosed embodiments the treatment gas may be used without aplasma. When the treatment gas includes water vapor, the delivery may beachieved using a mass flow meter (MFM), mass flow controller (MFC), aninjection valve, or by commercially available water vapor generators.The treatment gas may be introduced to the processing region 2033,either through the RPS unit or bypassing the RPS units, and may furtherbe excited in the first plasma region.

FIG. 6B shows a detailed view of the features affecting the processinggas distribution through faceplate 2017. As shown in FIGS. 6A and 6B,faceplate 2017, cooling plate 2003, and gas inlet assembly 2005intersect to define a gas supply region 2058 into which process gasesmay be delivered from gas inlet 2005. The gases may fill the gas supplyregion 2058 and flow to first plasma region 2015 through apertures 2059in faceplate 2017. The apertures 2059 may be configured to direct flowin a substantially unidirectional manner such that process gases mayflow into processing region 2033, but may be partially or fullyprevented from backflow into the gas supply region 2058 after traversingthe faceplate 2017.

The gas distribution assemblies such as showerhead 2025 for use in theprocessing chamber section 2000 may be referred to as dual channelshowerheads (DCSH) and are additionally detailed in the embodimentsdescribed in FIG. 6A as well as FIG. 7 herein. The dual channelshowerhead may provide for etching processes that allow for separationof etchants outside of the processing region 2033 to provide limitedinteraction with chamber components and each other prior to beingdelivered into the processing region.

The showerhead 2025 may comprise an upper plate 2014 and a lower plate2016. The plates may be coupled with one another to define a volume 2018between the plates. The coupling of the plates may be so as to providefirst fluid channels 2019 through the upper and lower plates, and secondfluid channels 2021 through the lower plate 2016. The formed channelsmay be configured to provide fluid access from the volume 2018 throughthe lower plate 2016 via second fluid channels 2021 alone, and the firstfluid channels 2019 may be fluidly isolated from the volume 2018 betweenthe plates and the second fluid channels 2021. The volume 2018 may befluidly accessible through a side of the gas distribution assembly 2025.Although the exemplary system of FIG. 6A includes a dual-channelshowerhead, it is understood that alternative distribution assembliesmay be utilized that maintain first and second precursors fluidlyisolated prior to the processing region 2033. For example, a perforatedplate and tubes underneath the plate may be utilized, although otherconfigurations may operate with reduced efficiency or not provide asuniform processing as the dual-channel showerhead as described.

In the embodiment shown, showerhead 2025 may distribute via first fluidchannels 2019 process gases which contain plasma effluents uponexcitation by a plasma in chamber plasma region 2015 or from RPS unit2001. In embodiments, the process gas introduced into the RPS unit 2001and/or chamber plasma region 2015 may contain fluorine, e.g., CF₄, NF₃,or XeF₂, oxygen, e.g. N₂O, or hydrogen-containing precursors, e.g. H₂ orNH₃. One or both process gases may also include a carrier gas such ashelium, argon, nitrogen (N₂), etc. Plasma effluents may include ionizedor neutral derivatives of the process gas and may also be referred toherein as a radical-fluorine precursor, referring to the atomicconstituent of the process gas introduced. In an example, afluorine-containing gas, such as NF₃, may be excited in the RPS unit2001 and passed through regions 2015 and 2033 without the additionalgeneration of plasmas in those regions. Plasma effluents from the RPSunit 2001 may pass through the showerhead 2025 and then react with thesubstrate 2055. After passing through the showerhead 2025, plasmaeffluents may include radical species and may be essentially devoid ofionic species or UV light. These plasma effluents may react with filmson the substrate 2055, e.g., titanium nitride and other maskingmaterial.

The gas distribution assemblies 2025 for use in the processing chambersection 2000 are referred to as dual channel showerheads (DCSH) and aredetailed in the embodiments described in FIG. 7 herein. The dual channelshowerhead may allow for flowable deposition of a material, andseparation of precursor and processing fluids during operation. Theshowerhead may alternatively be utilized for etching processes thatallow for separation of etchants outside of the reaction zone to providelimited interaction with chamber components and each other prior tobeing delivered into the processing region.

FIG. 7 is a bottom view of a showerhead 3025 for use with a processingchamber according to disclosed embodiments. Showerhead 3025 maycorrespond with the showerhead shown in FIG. 6A. Through-holes 3065,which show a view of first fluid channels 2019, may have a plurality ofshapes and configurations in order to control and affect the flow ofprecursors through the showerhead 3025. Small holes 3075, which show aview of second fluid channels 2021, may be distributed substantiallyevenly over the surface of the showerhead, even among the through-holes3065, which may help to provide more even mixing of the precursors asthey exit the showerhead than other configurations.

FIG. 8 shows a schematic cross-sectional view of an exemplary processingsystem 4000 according to embodiments of the present technology. System4000 may be a variation of system 100 in FIG. 1. System 4000 may alsoinclude variations on the chamber illustrated in FIG. 6A, and mayinclude some or all of the components illustrated in that figure. System4000 may include a processing chamber 4005 and a remote plasma unit4010. The remote plasma unit 4010 may be coupled with processing chamber4005 with one or more components. The remote plasma unit 4010 may becoupled with one or more of a remote plasma unit adapter 4015, anisolator 4020, a pressure plate 4025, and inlet adapter 4030, a diffuser4035, or a mixing manifold 4040. Mixing manifold 4040 may be coupledwith a top of processing chamber 4005, and may be coupled with an inletto processing chamber 4005.

Remote plasma unit adapter 4015 may be coupled with remote plasma unit4010 at a first end 4011, and may be coupled with isolator 4020 at asecond end 4012 opposite first end 4011. Through remote plasma unitadapter 4015 may define one or more channels. At first end 4011 may bedefined an opening or port to a channel 4013. Channel 4013 may becentrally defined within remote plasma unit adapter 4015, and may becharacterized by a first cross-sectional surface area in a directionnormal to a central axis through remote plasma unit adapter 4015, whichmay be in the direction of flow from the remote plasma unit 4010. Adiameter of channel 4013 may be equal to or in common with an exit portfrom remote plasma unit 4010. Channel 4013 may be characterized by alength from the first end 4011 to the second end 4012. Channel 4013 mayextend through the entire length of remote plasma unit adapter 4015, ora length less than the length from first end 4011 to second end 4012.For example, channel 4013 may extend less than halfway of the lengthfrom the first end 4011 to the second end 4012, channel 4013 may extendhalfway of the length from the first end 4011 to the second end 4012,channel 4013 may extend more than halfway of the length from the firstend 4011 to the second end 4012, or channel 4013 may extend abouthalfway of the length from the first end 4011 to the second end 4012 ofremote plasma unit adapter 4015.

Remote plasma unit adapter 4015 may also define one or more trenches4014 defined beneath remote plasma unit adapter 4015. Trenches 4014 maybe or include one or more annular recesses defined within remote plasmaunit adapter 4015 to allow seating of an o-ring or elastomeric element,which may allow coupling with an isolator 4020.

Isolator 4020 may be coupled with second end 4012 of remote plasma unitadapter 4015 in embodiments. Isolator 4020 may be or include an annularmember about an isolator channel 4021. Isolator channel 4021 may beaxially aligned with a central axis in the direction of flow throughremote plasma unit adapter 4015. Isolator channel 4021 may becharacterized by a second cross-sectional area in a direction normal toa direction of flow through isolator 4020. The second cross-sectionalarea may be equal to, greater than, or less than the firstcross-sectional area of channel 4013. In embodiments, isolator channel4021 may be characterized by a diameter greater than, equal to, or aboutthe same as a diameter of channel 4013 through remote plasma unitadapter 4015.

Isolator 4020 may be made of a similar or different material from remoteplasma unit adapter 4015, mixing manifold 4040, or any other chambercomponent. In some embodiments, while remote plasma unit adapter 4015and mixing manifold 4040 may be made of or include aluminum, includingoxides of aluminum, treated aluminum on one or more surfaces, or someother material, isolator 4020 may be or include a material that is lessthermally conductive than other chamber components. In some embodiments,isolator 4020 may be or include a ceramic, plastic, or other thermallyinsulating component configured to provide a thermal break between theremote plasma unit 4010 and the chamber 4005. During operation, remoteplasma unit 4010 may be cooled or operate at a lower temperaturerelative to chamber 4005, while chamber 4005 may be heated or operate ata higher temperature relative to remote plasma unit 4010. Providing aceramic or thermally insulating isolator 4020 may prevent or limitthermal, electrical, or other interference between the components.

Coupled with isolator 4020 may be a pressure plate 4025. Pressure plate4025 may be or include aluminum or another material in embodiments, andpressure plate 4025 may be made of or include a similar or differentmaterial than remote plasma unit adapter 4015 or mixing manifold 4040 inembodiments. Pressure plate 4025 may define a central aperture 4023through pressure plate 4025. Central aperture 4023 may be characterizedby a tapered shape through pressure plate 4025 from a portion proximateisolator channel 4021 to the opposite side of pressure plate 4025. Aportion of central aperture 4023 proximate isolator channel 4021 may becharacterized by a cross-sectional area normal a direction of flow equalto or similar to a cross-sectional area of isolator channel 4021.Central aperture 4023 may be characterized by a percentage of taper ofgreater than or about 10% across a length of pressure plate 4025, andmay be characterized by a percentage of taper greater than or about 20%,greater than or about 30%, greater than or about 40%, greater than orabout 50%, greater than or about 60%, greater than or about 70%, greaterthan or about 80%, greater than or about 90%, greater than or about100%, greater than or about 150%, greater than or about 200%, greaterthan or about 300%, or greater in embodiments. Pressure plate 4025 mayalso define one or more trenches 4024 defined beneath isolator 4020.Trenches 4024 may be or include one or more annular recesses definedwithin pressure plate 4025 to allow seating of an o-ring or elastomericelement, which may allow coupling with isolator 4020.

An inlet adapter 4030 may be coupled with pressure plate 4025 at a firstend 4026, and coupled with diffuser 4035 at a second end 4027 oppositefirst end 4026. Inlet adapter 4030 may define a central channel 4028defined through inlet adapter 4030. Central channel 4028 may becharacterized by a first portion 4029 a, and a second portion 4029 b.First portion 4029 a may extend from first end 4026 to a first lengththrough inlet adapter 4030, wherein central channel 4028 may transitionto second portion 4029 b, which may extend to second end 4027. Firstportion 4029 a may be characterized by a first cross-sectional area ordiameter, and second portion 4029 b may be characterized by a secondcross-sectional area or diameter less than the first. In embodiments thecross-sectional area or diameter of first portion 4029 a may be twice aslarge as the cross-sectional area or diameter of second portion 4029 b,and may be up to or greater than about three times as large, greaterthan or about 4 times as large, greater than or about 5 times as large,greater than or about 6 times as large, greater than or about 7 times aslarge, greater than or about 8 times as large, greater than or about 9times as large, greater than or about 10 times as large, or greater inembodiments. Central channel 4028 may be configured to provide plasmaeffluents of a precursor delivered from remote plasma unit 4010 inembodiments, which may pass through channel 4013 of remote plasma unitadapter 4015, isolator channel 4021 of isolator 4020, and centralaperture 4023 of pressure plate 4025.

Inlet adapter 4030 may also define one or more second channels 4031,which may extend from below first portion 4029 a to or through secondend 4027. The second channels 4031 may be characterized by a secondcross-sectional surface area in a direction normal to the central axisthrough inlet adapter 4030. The second cross-sectional surface area maybe less than the cross-sectional surface area of first portion 4029 a inembodiments, and may be greater than the cross-sectional surface area ora diameter of second portion 4029 b. Second channels 4031 may extend toan exit from inlet adapter 4030 at second end 4027, and may provideegress from adapter 4030 for a precursor, such as a first bypassprecursor, delivered alternately from the remote plasma unit 4010. Forexample, second channel 4031 may be fluidly accessible from a first port4032 defined along an exterior surface, such as a side, of inlet adapter4030, which may bypass remote plasma unit 4010. First port 4032 may beat or below first portion 4029 a along a length of inlet adapter 4030,and may be configured to provide fluid access to the second channel4031.

Second channel 4031 may deliver the precursor through the inlet adapter4030 and out second end 4027. Second channel 4031 may be defined in aregion of inlet adapter 4030 between first portion 4029 a and second end4027. In embodiments, second channel 4031 may not be accessible fromcentral channel 4028. Second channel 4031 may be configured to maintaina precursor fluidly isolated from plasma effluents delivered intocentral channel 4028 from remote plasma unit 4010. The first bypassprecursor may not contact plasma effluents until exiting inlet adapter4030 through second end 4027. Second channel 4031 may include one ormore channels defined in adapter 4030. Second channel 4031 may becentrally located within adapter 4030, and may be associated withcentral channels 4028. For example, second channel 4031 may beconcentrically aligned and defined about central channel 4028 inembodiments. Second channel 4031 may be an annular or cylindricalchannel extending partially through a length or vertical cross-sectionof inlet adapter 4030 in embodiments. In some embodiments, secondchannel 4031 may also be a plurality of channels extending radiallyabout central channel 4028.

Inlet adapter 4030 may also define one or more third channels 4033,which may extend from below first portion 4029 a to or through secondend 4027, and may extend from below a plane bisecting first port 4032.The third channels 4033 may be characterized by a third cross-sectionalsurface area in a direction normal to the central axis through inletadapter 4030. The third cross-sectional surface area may be less thanthe cross-sectional surface area of first portion 4029 a in embodiments,and may be greater than the cross-sectional surface area or a diameterof second portion 4029 b. The third cross-sectional surface area mayalso be equal to or similar to the cross-sectional surface area or adiameter of first portion 4029 a as illustrated. For example, an outerdiameter of third channel 4033 may be equivalent to an outer diameter offirst portion 4029 a, or may be less than an outer diameter of firstportion 4029 a. Third channels 4033 may extend to an exit from inletadapter 4030 at second end 4027, and may provide egress from adapter4030 for a precursor, such as a second bypass precursor, deliveredalternately from the remote plasma unit 4010. For example, third channel4033 may be fluidly accessible from a second port 4034 defined along anexterior surface, such as a side, of inlet adapter 4030, which maybypass remote plasma unit 4010. Second port 4034 may be located on anopposite side or portion of inlet adapter 4030 as first port 4032.Second port 4034 may be at or below first portion 4029 a along a lengthof inlet adapter 4030, and may be configured to provide fluid access tothe third channel 4033. Second port 4034 may also be at or below firstport 4032 along a length of inlet adapter 4030 in embodiments.

Third channel 4033 may deliver the second bypass precursor through theinlet adapter 4030 and out second end 4027. Third channel 4033 may bedefined in a region of inlet adapter 4030 between first portion 4029 aand second end 4027. In embodiments, third channel 4033 may not beaccessible from central channel 4028. Third channel 4033 may beconfigured to maintain a second bypass precursor fluidly isolated fromplasma effluents delivered into central channel 4028 from remote plasmaunit 4010, and from a first bypass precursor delivered into secondchannel 4031 through first port 4032. The second bypass precursor maynot contact plasma effluents or a first bypass precursor until exitinginlet adapter 4030 through second end 4027. Third channel 4033 mayinclude one or more channels defined in adapter 4030. Third channel 4033may be centrally located within adapter 4030, and may be associated withcentral channels 4028 and second channel 4031. For example, thirdchannel 4033 may be concentrically aligned and defined about centralchannel 4028 in embodiments, and may be concentrically aligned anddefined about second channel 4031. Third channel 4033 may be a secondannular or cylindrical channel extending partially through a length orvertical cross-section of inlet adapter 4030 in embodiments. In someembodiments, third channel 4033 may also be a plurality of channelsextending radially about central channel 4028.

Diffuser 4035 may be positioned between inlet adapter 4030 and mixingmanifold 4040 to maintain precursors delivered through inlet adapter4030 fluidly isolated until accessing mixing manifold 4040. Diffuser4035 may be characterized by one or more channels, such as cylindricalor annular channels defined through diffuser 4035. In embodiments,diffuser 4035 may define a first channel 4036 or central channel, asecond channel 4037, and a third channel 4038. The channels may becharacterized by similar dimensions or diameters as second portion 4029b of central channel 4028, second channel 4031, and third channel 4033of inlet adapter 4030. For example, each channel may extend the inletadapter channels to mixing manifold 4040. Second channel 4037 and thirdchannel 4038 may each be annular channels defined about first channel4036, and first channel 4036, second channel 4037, and third channel4038 may be concentrically aligned in embodiments and defined throughdiffuser 4035.

Diffuser 4035 may additionally define one or more trenches 4039 aboutdiffuser 4035. For example, diffuser 4035 may define a first trench 4039a, a second trench 4039 b, and a third trench 4039 c in embodiments,which may allow seating of o-rings or elastomeric members between inletadapter 4030 and diffuser 4035. Each of trenches 4039 may be an annulartrench in embodiments that sits radially exterior to one or more of thechannels defined through diffuser 4035. First trench 4039 a may belocated radially outward of first channel 4036, and may be locatedbetween first channel 4036 and second channel 4037. Second trench 4039 bmay be located radially outward of second channel 4037, and may belocated between second channel 4037 and third channel 4038. Third trench4039 c may be located radially outward of third channel 4038. A diameterof each trench 4039 may be greater than the channel to which it may beassociated and to which it may be located radially exterior. Thetrenches may enable improved sealing between the inlet adapter 4030 andthe diffuser 4035 to ensure precursors are maintained fluidly isolatedbetween the components, and leaking between the channels does not occur.

Mixing manifold 4040 may be coupled with diffuser 4035 at a first end4041, and may be coupled with chamber 4005 at a second end 4042. Mixingmanifold 4040 may define an inlet 4043 at first end 4041. Inlet 4043 mayprovide fluid access from diffuser 4035, and inlet 4043 may becharacterized by a diameter equal to or about the same as a diameter ofthird channel 4038 through diffuser 4035. Inlet 4043 may define aportion of a channel 4044 through mixing manifold 4040, and the channel4044 may be composed of one or more sections defining a profile ofchannel 4044. Inlet 4043 may be a first section in the direction of flowthrough channel 4044 of mixing manifold 4040. Inlet 4043 may becharacterized by a length that may be less than half a length in thedirection of flow of mixing manifold 4040. The length of inlet 4043 mayalso be less than a third of the length of mixing manifold 4040, and maybe less than one quarter the length of mixing manifold 4040 inembodiments. Inlet 4043 may receive each precursor from diffuser 4035,and may allow for mixing of the precursors, which may have beenmaintained fluidly isolated until delivery to mixing manifold 4040.

Inlet 4043 may extend to a second section of channel 4044, which may beor include a tapered section 4045. Tapered section 4045 may extend froma first diameter equal to or similar to a diameter of inlet 4043 to asecond diameter less than the first diameter. In some embodiments, thesecond diameter may be about or less than half the first diameter.Tapered section 4045 may be characterized by a percentage of taper ofgreater than or about 10%, greater than or about 20%, greater than orabout 30%, greater than or about 40%, greater than or about 50%, greaterthan or about 60%, greater than or about 70%, greater than or about 80%,greater than or about 90%, greater than or about 100%, greater than orabout 150%, greater than or about 200%, greater than or about 300%, orgreater in embodiments.

Tapered section 4045 may transition to a third region of channel 4044,which may be a flared section 4046. Flared section 4046 may extend fromtapered section 4045 to an outlet of mixing manifold 4040 at second end4042. Flared section 4046 may extend from a first diameter equal to thesecond diameter of tapered section 4045 to a second diameter greaterthan the first diameter. In some embodiments, the second diameter may beabout or greater than double the first diameter. Flared section 4046 maybe characterized by a percentage of flare of greater than or about 10%,greater than or about 20%, greater than or about 30%, greater than orabout 40%, greater than or about 50%, greater than or about 60%, greaterthan or about 70%, greater than or about 80%, greater than or about 90%,greater than or about 100%, greater than or about 150%, greater than orabout 200%, greater than or about 300%, or greater in embodiments.

Flared section 4046 may provide egress to precursors delivered throughmixing manifold 4040 through second end 4042 via an outlet 4047. Thesections of channel 4044 through mixing manifold 4040 may be configuredto provide adequate or thorough mixing of precursors delivered to themixing manifold, before providing the mixed precursors into chamber44005. Unlike conventional technology, by performing the etchant orprecursor mixing prior to delivery to a chamber, the present systems mayprovide an etchant having uniform properties prior to being distributedabout a chamber and substrate. In this way, processes performed with thepresent technology may have more uniform results across a substratesurface.

Processing chamber 4005 may include a number of components in a stackedarrangement. The chamber stack may include a gasbox 4050, a blockerplate 4060, a faceplate 4070, an ion suppression element 4080, and a lidspacer 4090. The components may be utilized to distribute a precursor orset of precursors through the chamber to provide a uniform delivery ofetchants or other precursors to a substrate for processing. Inembodiments, these components may be stacked plates each at leastpartially defining an exterior of chamber 4005.

Gasbox 4050 may define a chamber inlet 4052. A central channel 4054 maybe defined through gasbox 4050 to deliver precursors into chamber 4005.Inlet 4052 may be aligned with outlet 4047 of mixing manifold 4040.Inlet 4052 and/or central channel 4054 may be characterized by a similardiameter in embodiments. Central channel 4054 may extend through gasbox4050 and be configured to deliver one or more precursors into a volume4057 defined from above by gasbox 4050. Gasbox 4050 may include a firstsurface 4053, such as a top surface, and a second surface 4055 oppositethe first surface 4053, such as a bottom surface of gasbox 4050. Topsurface 4053 may be a planar or substantially planar surface inembodiments. Coupled with top surface 4053 may be a heater 4048.

Heater 4048 may be configured to heat chamber 4005 in embodiments, andmay conductively heat each lid stack component. Heater 4048 may be anykind of heater including a fluid heater, electrical heater, microwaveheater, or other device configured to deliver heat conductively tochamber 4005. In some embodiments, heater 4048 may be or include anelectrical heater formed in an annular pattern about first surface 4053of gasbox 4050. The heater may be defined across the gasbox 4050, andaround mixing manifold 4040. The heater may be a plate heater orresistive element heater that may be configured to provide up to, about,or greater than about 2,000 W of heat, and may be configured to providegreater than or about 2,500 W, greater than or about 3,000 W, greaterthan or about 3,500 W, greater than or about 4,000 W, greater than orabout 4,500 W, greater than or about 5,000 W, or more.

Heater 4048 may be configured to produce a variable chamber componenttemperature up to, about, or greater than about 50° C., and may beconfigured to produce a chamber component temperature greater than orabout 75° C., greater than or about 100° C., greater than or about 150°C., greater than or about 200° C., greater than or about 250° C.,greater than or about 300° C., or higher in embodiments. Heater 4048 maybe configured to raise individual components, such as the ionsuppression element 4080, to any of these temperatures to facilitateprocessing operations, such as an anneal. In some processing operations,a substrate may be raised toward the ion suppression element 4080 for anannealing operation, and heater 4048 may be adjusted to conductivelyraise the temperature of the heater to any particular temperature notedabove, or within any range of temperatures within or between any of thestated temperatures.

Second surface 4055 of gasbox 4050 may be coupled with blocker plate4060. Blocker plate 4060 may be characterized by a diameter equal to orsimilar to a diameter of gasbox 4050. Blocker plate 4060 may define aplurality of apertures 4063 through blocker plate 4060, only a sample ofwhich are illustrated, which may allow distribution of precursors, suchas etchants, from volume 4057, and may begin distributing precursorsthrough chamber 4005 for a uniform delivery to a substrate. Althoughonly a few apertures 4063 are illustrated, it is to be understood thatblocker plate 4060 may have any number of apertures 4063 defined throughthe structure. Blocker plate 4060 may be characterized by a raisedannular section 4065 at an external diameter of the blocker plate 4060,and a lowered annular section 4066 at an external diameter of theblocker plate 4060. Raised annular section 4065 may provide structuralrigidity for the blocker plate 4060, and may define sides or an externaldiameter of volume 4057 in embodiments. Blocker plate 4060 may alsodefine a bottom of volume 4057 from below. Volume 4057 may allowdistribution of precursors from central channel 4054 of gasbox 4050before passing through apertures 4063 of blocker plate 4060. Loweredannular section 4066 may also provide structural rigidity for theblocker plate 4060, and may define sides or an external diameter of asecond volume 4058 in embodiments. Blocker plate 4060 may also define atop of volume 4058 from above, while a bottom of volume 4058 may bedefined by faceplate 4070 from below.

Faceplate 4070 may include a first surface 4072 and a second surface4074 opposite the first surface 4072. Faceplate 4070 may be coupled withblocker plate 4060 at first surface 4072, which may engage loweredannular section 4066 of blocker plate 4060. Faceplate 4070 may define aledge 4073 at an interior of second surface 4074, extending to thirdvolume 4075 at least partially defined within or by faceplate 4070. Forexample, faceplate 4070 may define sides or an external diameter ofthird volume 4075 as well as a top of volume 4075 from above, while ionsuppression element 4080 may define third volume 4075 from below.Faceplate 4070 may define a plurality of channels through the faceplate,such as previously described with chamber 2000, although not illustratedin FIG. 8.

Ion suppression element 4080 may be positioned proximate the secondsurface 4074 of faceplate 4070, and may be coupled with faceplate 4070at second surface 4074. Ion suppression element 4080 may be similar toion suppressor 2023 described above, and may be configured to reduceionic migration into a processing region of chamber 4005 housing asubstrate. Ion suppression element 4080 may define a plurality ofapertures through the structure as illustrated in FIG. 6A, although notillustrated in FIG. 8. In embodiments, gasbox 4050, blocker plate 4060,faceplate 4070, and ion suppression element 4080 may be coupledtogether, and in embodiments may be directly coupled together. Bydirectly coupling the components, heat generated by heater 4048 may beconducted through the components to maintain a particular chambertemperature that may be maintained with less variation betweencomponents. Ion suppression element 4080 may also contact lid spacer4090, which together may at least partially define a plasma processingregion in which a substrate is maintained during processing.

Turning to FIG. 9 is illustrated a bottom partial plan view of an inletadapter 5000 according to embodiments of the present technology. Inletadapter 5000 may be similar to inlet adapter 4030 in embodiments. Asillustrated, inlet adapter may include three channels concentricallyaligned about a central axis of inlet adapter 5000. It is to beunderstood that in other embodiments the inlet adapter 5000 may includemore or fewer channels than illustrated. Inlet adapter 5000 may includea central channel 5005 that may be fluidly accessible from a remoteplasma unit as previously discussed. Central channel 5005 may extendfully through inlet adapter 5000. Second channel 5010 may extend aboutcentral channel 5005 and may provide fluid access for a first bypassprecursor delivered additionally or alternatively with plasma effluentsof a precursor through central channel 5005. Second channel 5010 may beaccessed from first port 5012 defined along an exterior of inlet adapter5000. Second channel 5010 may be concentrically aligned with centralchannel 5005, and may maintain a first bypass precursor fluidly isolatedfrom plasma effluents or a different precursor flowing through centralchannel 5005.

Third channel 5015 may extend about central channel 5005 and secondchannel 5010, and may provide fluid access for a second bypass precursordelivered additionally or alternatively with plasma effluents of aprecursor through central channel 5005 and a first bypass precursorthrough second channel 5010. Third channel 5015 may be accessed from asecond port 5017 defined along an exterior of inlet adapter 5000, whichmay be located on a side of inlet adapter 5000 opposite first port 5012.Second port 5017 as well as third channel 5015 may be located below ahorizontal plane through first port 5012. Third channel 5015 may beconcentrically aligned with central channel 5005, and may maintain asecond bypass precursor fluidly isolated from plasma effluents or adifferent precursor flowing through central channel 5005, and a firstbypass precursor delivered through second channel 5010.

Both second channel 5010 and third channel 5015 may be annular channeldefined at least partially through a length of inlet adapter 5000 inembodiments. The channels may also be a plurality of channels definedradially about central channel 5005. By providing three separatepathways for precursors, different volumes and/or flow rates ofprecursors may be utilized providing greater control over precursordelivery and etchant generation. Each precursor may be delivered withone or more carrier gases, and etchant developed may be finely tunedprior to delivery into a processing chamber fluidly coupled with inletadapter 5000.

The above description of example embodiments of the invention has beenpresented for the purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the precise formdescribed, and many modifications and variations are possible in lightof the teaching above.

In the preceding description, for the purposes of explanation, numerousdetails have been set forth in order to provide an understanding ofvarious embodiments of the present technology. It will be apparent toone skilled in the art, however, that certain embodiments may bepracticed without some of these details, or with additional details.

Having described several embodiments, it will be recognized by those ofskill in the art that various modifications, alternative constructions,and equivalents may be used without departing from the spirit of theinvention. Additionally, a number of well-known processes and elementshave not been described in order to avoid unnecessarily obscuring thepresent invention. Additionally, details of any specific embodiment maynot always be present in variations of that embodiment or may be addedto other embodiments.

Where a range of values is provided, it is understood that eachintervening value, to the tenth of the unit of the lower limit unlessthe context clearly dictates otherwise, between the upper and lowerlimits of that range is also specifically disclosed. Each smaller rangebetween any stated value or intervening value in a stated range and anyother stated or intervening value in that stated range is encompassed.The upper and lower limits of these smaller ranges may independently beincluded or excluded in the range, and each range where either, neither,or both limits are included in the smaller ranges is also encompassedwithin the invention, subject to any specifically excluded limit in thestated range. Where the stated range includes one or both of the limits,ranges excluding either or both of those included limits are alsoincluded.

As used herein and in the appended claims, the singular forms “a”, “an”,and “the” include plural referents unless the context clearly dictatesotherwise. Thus, for example, reference to “a method” includes aplurality of such methods and reference to “the layer” includesreference to one or more layers and equivalents thereof known to thoseskilled in the art, and so forth. The invention has now been describedin detail for the purposes of clarity and understanding. However, itwill be appreciated that certain changes and modifications may bepractice within the scope of the appended claims.

All publications, patents, and patent applications cited herein arehereby incorporated by reference in their entirety for all purposes.None is admitted to be prior art.

What is claimed is:
 1. A semiconductor processing system, the systemcomprising: a remote plasma region; a showerhead, wherein the showerheadat least partially defines a processing region fluidly coupled with theremote plasma region; an inlet adapter positioned between the remoteplasma region and the showerhead and defining a channel, wherein theinlet adapter is free of nickel plating; a mixing manifold positionedbetween the inlet adapter and the showerhead, wherein the mixingmanifold comprises nickel; and a pedestal extending into the processingregion, wherein the processing region is further defined about anexterior by a sidewall, and wherein the sidewall and showerhead areplated with nickel.
 2. The system of claim 1, wherein the processingregion is defined by surfaces plated with nickel from the channel, butnot including the channel, to an exit from the processing region leadingto a pump.
 3. The system of claim 1, further comprising an annulusdisposed on the pedestal, wherein the annulus is plated with nickel. 4.The system of claim 1, further comprising: an isolator positionedbetween the remote plasma region and the inlet adapter.
 5. The system ofclaim 4, wherein the isolator is free of nickel plating.
 6. The systemof claim 4, further comprising: a second adapter positioned between theremote plasma region and the inlet adapter, wherein the second adapteris free of nickel plating.
 7. The system of claim 1, wherein the inletadapter defines a first flow path from the remote plasma region, andwherein the inlet adapter defines a second flow path bypassing theremote plasma region.
 8. The system of claim 7, wherein the first flowpath and the second flow path are maintained fluidly isolated throughthe inlet adapter.
 9. The system of claim 8, wherein the first flow pathand the second flow path deliver to the mixing manifold to mix fluidsflowed along the first flow path and the second flow path.
 10. Thesystem of claim 1, further comprising: a gasbox positioned between theinlet adapter and the processing region, wherein the gasbox comprisesnickel.
 11. The system of claim 10, further comprising: a blocker platepositioned between the gasbox and the processing region, wherein thegasbox comprises nickel.
 12. A semiconductor processing system, thesystem comprising: a remote plasma region; a processing chamber fluidlycoupled with the remote plasma region, the processing chambercomprising: a showerhead, wherein the showerhead at least partiallydefines a processing region, and a spacer defining an exterior radius ofthe processing region, wherein the showerhead and an interior surface ofthe spacer comprises nickel; an inlet adapter positioned between theremote plasma region and the processing chamber, wherein the inletadapter is free of nickel plating; and a mixing manifold positionedbetween the inlet adapter and the processing chamber, wherein the mixingmanifold comprises nickel.
 13. The system of claim 12, wherein the inletadapter defines a first flow path from the remote plasma region, andwherein the inlet adapter defines a second flow path bypassing theremote plasma region.
 14. The system of claim 13, wherein the first flowpath and the second flow path are maintained fluidly isolated throughthe inlet adapter.
 15. The system of claim 14, wherein the first flowpath and the second flow path fluidly couple with the mixing manifold tomix fluids flowed along the first flow path and the second flow path.16. The system of claim 12, wherein no components upstream of the mixingmanifold include nickel plating.
 17. The system of claim 12, whereineach component downstream of the inlet adapter comprises nickel.
 18. Thesystem of claim 12, wherein the processing chamber further comprises: apedestal extending into the processing region.
 19. The system of claim12, further comprising: an edge ring seated about an exterior of thepedestal, wherein the edge ring comprises nickel.
 20. A semiconductorprocessing system comprising: a remote plasma region; a showerhead,wherein the showerhead at least partially defines a processing regionfluidly coupled with the remote plasma region, wherein the processingregion is radially defined by a sidewall, and wherein the sidewall andshowerhead are plated with nickel; an inlet adapter positioned betweenthe remote plasma region and the showerhead and defining a channel,wherein the inlet adapter is free of nickel plating; and a mixingmanifold positioned between the inlet adapter and the showerhead,wherein the mixing manifold comprises nickel.